Method for lining track in a track curve

ABSTRACT

A mobile track liner comprises a laser beam gun in an uncorrected track section emitting a reference beam forming a chord in the arc of a track curve, and a laser beam receiver mounted on the liner, laser beam gun and receiver are transversely adjustable in relation to fixed points, such as telegraph poles and like markers defining a planned track position and respectively associated with the laser beam gun and the receiver. A control means for the track lining converts lining error signals which are a function of the receiver position in dependence of the length of the path of the movement of the receiver on the track into lining control signals. In the lining method, the receiver on the liner is moved towards the laser beam gun which is mounted on a carriage in the uncorrected track section.

United States Patent Plasser et al. Sept. 2, 1975 [54] METHOD FOR LINING TRACK IN A 3,605,625 9/l97l Bencsics 104/8 TRACK CURVE [76] Inventors: Franz Plasser; Josef Theurer, both gfxysg g g z s g ggg gg of Johannesgasse 3, A-lOlO Vienna, Atwme A K y, gent, or zrm urt elman Austria [22] Filed: Feb. 13, 1974 [57] ABSTRACT [21] APPL 442,096 A mobile track liner comprises a laser beam gun in an uncorrected track section emitting a reference beam Related Apphcanon Data forming a chord in the arc of a track curve, and a laser [62] Division of Ser. No. 313,745, Dec. 11, 1972, Pat. No. beam receiver mounted on the liner, laser beam gun 3,821,933 and receiver are transversely adjustable in relation to fixed points, such as telegraph poles and like markers Foreign Application Priority Data defining a planned track position and respectively as- Feb. 7, 1972 Austria 972/72 sociated with the laser beam gun and the receiver. A control means for the track lining converts lining error [52] US. Cl. 104/8 signals which are a function of the receiver position in [51 Int. Cl EOlb 32/02 dependence of the length of the path of the movement [58] Field of Search 104/7, 7 B, 8; 33/47, 60 of the receiver on the track into lining control signals. In the lining method, the receiver on the liner is [56] References Cited moved towards the laser beam gun which is mounted UNITED STATES PATENTS on a carriage in the uncorrected track section.

3,604,360 9/ 1971 Stewart et a] 104/8 12 Claims, 11 Drawing Figures PATENTH] SE? 2 9.75

SHEET 2 BF 3 METHOD FOR LINING CK IN A E CURVE This is a division of application Ser. No. 313,745 filed Dec. 11, 1972, now US. Pat. No. 3,821,933.

The present invention relates to improvements in a method for lining a track in a track curve in respect of a laser reference beam forming an accurate chord in the arc of the track curve. In such track lining methods, the actual ordinate of the surveyed track points is compared with the planned ordinate of these points, these planned ordinates being established, for instance, on a track map, and the difference between the actual and the planned ordinates serves to determine the extent of the lining.

In one known track lining method of this type, an emitter of an infrared reference beam is arranged on an independent carriage in the track curve, and the associated receiver of the reference beam is arranged at the rear end of the track liner following the carriage. Emitter and receiver are held at a fixed transverse distance from the track. The reference beam forms a chord of known length in the track curve arc. Since the radius of the arc is also known, the required ordinate of each track curve point may be calculated readily. The desired ordinate of each point may be adjusted by a laterally movable stop in the path of the beam, and the lining tools are operated until the stop is aligned with the beam.

Since infrared beams are conical and rather diffuse, and require not only an emitter and receiver but also an intermediate stop, they can be used only for short distances. If a long curve is lined in this manner by a sequence of successive lining operations, the totality of the track curve position is changed in an uncontrollable manner.

A more accurate final track position is obtained if track curves are lined in respect of fixed track points defining the planned position. It has, therefore, been proposed to line tangent track as well as track curves in relation to fixed points which are marked along the right of way or on a track map. In such known lining systems, markers are erected at the fixed points to form a visible reference line, and the markers are sighted from the liner to determine deviations from the planned track position. These deviations are then eliminated by corresponding lining of the track.

It has also been proposed to use laser reference beams in track lining, particularly in tangent track, for instance, in applicants US patent application Ser. No. 3762, filed Jan. 19, 1970, now US. Pat. No. 3,706,284.

It is the primary object of this invention to line tracks in relation to relatively widely spaced fixed points, i.e. fixed points spaced apart between and 80 meters, or more, with increased accuracy in determining lining errors and correcting the same.

This object is accomplished in accordance with the invention by positioning an emitter and receiver of the reference beam in relation to fixed points of the track respectively associated with the emitter and receiver, the emitter being positioned in an uncorrected track section, and thereupon moving the receiver on the track towards the emitter. The value of deviation of the track, i.e. the lining error parameter, from the planned position of the track, as indicated by the reference beam, is determined in dependence on the length of the path of movement of the receiver by adjusting the receiver or emitter in respect of each other.

The lining operation may be automated while assuring highest accuracy and operational speed, particularly in the lining of track curves, by continuously positioning the receiver in relation to the associated fixed track point either by sensing the reference beam by laterally moving the receiver while moving it on the track, or by pivoting the receiver about an angle determined by the planned ordinate and the length of the path of movement of the receiver.

It is also advantageous to prepare a lining program for an entire track section to be lined in advance by storing the determined values of track deviation on information storage element, such as a punched tape, which information may then be retrieved on a track liner for controlling the extent of lining in response to the stored values while the liner advances without interruption along the track section. Alternatively, the information is determined and simultaneously fed to the liner so that surveying and lining proceed at the same time.

The above and other objects, advantages and features of this invention will become more apparent from the following detailed description of certain now preferred embodiments thereof, taken in conjunction with the accompanying drawing wherein FIGS. I and 2 are schematic plan views of two modes of use of a mobile track position correction machine according to the invention;

FIG. 3 is a plan view of such a machine on an enlarged scale and showing some structural details;

FIGS. 3a to 3c illustrate parts of the machine of FIG. 3 on an enlarged scale in elevational side views;

F IG. 4 is similar to FIG. 3 and shows another embodiment constituted by a combined track lining, leveling and tamping machine;

FIG. 5 similarly shows yet another embodiment used in the scheme of FIG. 1; and

FIGS. 6 to 8 similarly show additional embodiments used in the scheme of FIG. 2.

Referring now to the drawing, wherein like reference numerals designate like parts functioning in a like manner in all figures, FIGS. 1 and 2 purely schematically illustrate the principles of the invention. As shown, a laser beam gun 2 is positioned in an uncorrected section of track I in relation to a fixed point 3 associated therewith, such as a telegraph pole, a marking post or the like, on a carriage mounted for mobility on the track. The laser beam gun emits a reference laser beam in the direction of receiver 5 which constitutes a target or sensor for the laser beam.

In the embodiment of FIG. I, the laser beam receiver 5 is mounted on track liner 6 substantially at the point 1 where the track is to be lined. Starting from another fixed point 7, with which the receiver 5 is associated, the liner 6 has previously lined another section of the track 1, moving during the lining operation towards the laser beam gun.

Accurate lining of the track curve is achieved by laterally adjusting, i.e. pivoting, laser beam gun 2 in dependence on the length of the path of movement of the receiver 5 on the track after each forward movement of the liner or at least before each lining operation. During this intermittent advance of the liner on the track curve, the control unit 8 pivots the laser beam gun so that the differences in the ordinates between two successive lining points are taken into consideration.

In the embodiment of FIG. 1, the control unit 8 is connected to the laser beam gun pivoting means by control line 9 to pivot the gun, whereupon the laser beam receiver or target is laterally moved in the direction of arrow 11 transversely of the track until the laser beam 4 emitted from gun 2 is in alignment with the target or receiver 5, at which point the track is in the planned or corrected position. The lateral movement of the receiver 5 is effected by laterally moving the track 1 by track lining means mounted on liner 6, the liner moving with the track and the receiver moving with the liner on which it is mounted. Thus, the track and the laser beam receiver are in the desired or planned position of the track.

In the embodiment of FIG. 2, the track liner is incorporated in a combined lining, leveling and tamping machine 6 which has its own reference system 12 which may consist of a light beam, for instance. Such a known reference system extends from a rear end point, as seen in the working direction indicated by arrow 13, which is located in a previously corrected track section to a forward end point 14 ahead of the machine in an uncorrected track section. In this embodiment, the laser beam sensor 5 is transversely movable together with the forward end point of reference system 12 in the direction of arrow 10.

In operation, the control unit 8 again laterally adjusts the laser beam gun 2 before each adjustment of receiver 5 according to data derived from the planned track position or a map of the desired track position. However, in contrast to the embodiment of FIG. 1, only the receiver 5, together with reference system end point 14, are aligned with laser beam 12 in the direction of arrow 4 without laterally moving the track. After this adjustment, the forward as well as the rear ends of reference system 12 are in the planned position reflecting the desired position of the track. This enables the track to be lined by machine 6 in the direction of arrow 11 to assume its planned position.

Additional control line 9' is provided in both embodiments to prevent the lateral movement of track 1 or the end point 14 of the reference system for the track lining to be effected before the position of the laser beam gun has been laterally adjusted. In both embodiments, the laser beam gun 2 and the reciever 5 are positioned at the beginning of the lining operation in relation to fixed points 3 and 7, respectively, and the laser beam gun 2 is brought into alignment with the target or sensor 5 after the laser beam gun and the receiver have been moved into the correct distances from their associated fixed points, such distances being determined by the planned position of the track. The liners 6, 6 then move in working direction 13, together with the receiver 5 mounted thereon, until the receiver comes close to fixed point 3. At this stage, the laser beam gun 2 is moved in the working direction to a succeeding fixed point defining the planned track position, whereupon the next cycle of operations starts.

FIG. 3 shows the details of a track liner useful in the operation schematically illustrated in FIG. 1, the actual position of rails 15, 16 of track 1 being shown in full lines and the deviation of the track from the planned position, i.e. the lining error, being indicated by the difference in the full and broken lines of the rails. A carriage 17 is mounted on flanged wheels 18, 19 for mobility on the track and is positioned adjacent fixed point 3. Carriage 17 carries a scale 20 for determining the lateral adjustment in relation to fixed point 3 and a laser beam gun 2 which is arranged for lateral movement transversely of the track as well as for pivoting movement for assuming a desired angle in relation to the track axis. In a known manner, the carriage 17 may be pressed with its flanged wheels into selective engagement with one of the rails 15 or 16 selected as the grade rail for the lining operation. In the illustrated embodiment, the grade rail is outer rail 15 of the track in the curve so that the flanged wheel 18 engages rail 15.

Suitable track lining means, such as laterally movable rail engaging rollers 21, are positioned close to fixed point 7, jack 22 being arranged to press the rail engaging rollers in a selected lateral direction to line track 1. Laser beam target or sensor 5 is mounted laterally adjustably on a carriage 23 mounted for mobility on the track with the track lining means, the carriage also carrying a fixed scale 20 which enables the lateral adjustment of the receiver 5 in relation to associated fixed point 7. The carriage also has an odometer 40 rolling on rail 16 to determine the length of the path of movement of carriage 23 on the track, the odometer including an inductive signal emitter indicating the distance traveled by the carriage.

The apparatus of FIG. 3 operates as follows:

The planned track position is indicated beforehand on track map 26 and, at the beginning of the operation, i.e. either track lining or track surveying, the laser beam gun 2 and the receiver 5' are laterally positioned in relation to respective fixed points 3 and 7 in the direction of double-headed arrows 24, 25 so that the distance between the fixed points and the planned track axis 27 is x, and x as determined by the map 26, use being made of scales 20, 20' for this lateral adjustment.

The lining error f, i.e. the distance between the actual and desired or planned track position, in the region of the laser beam gun determines the lateral movement of the gun in respect of scale 20 in the direction of fixed point 3 until the gun has the desired distance x The laser beam receiver 5' is then moved on the track towards the laser beam gun 2 in the direction of arrow 13, i.e. in the working direction, by length y of the path of movement of the receiver into position 28 indicated in broken lines. Before the track can be lined or the lining error determined in this position, the laser beam 4 must be adjusted according to the changes in the ordinate or height of the are which depend on the length of distance y, and the arc radius which appears on map 26. This adjustment is effected by pivoting the laser beam gun in the direction of double-headed arrow 29 about a vertical axis through angle 02,, as can be seen in the adjustment diagram associated with FIG. 3.

The angular adjustment of the laser gun may be effectuated by an operator 30 who reads the values of the distance z between the fixed points as well as the arc radius R from the track map 26, as well as the traveled distance y, from the distance indicator 31 connected to the inductive signal emitter of odometer 40, and feeds these values into a computer 32. This computer is programmed to determine the pivoting angle of the laser beam gun 2' for each position of receiver 5', control line 33 or radio transmitter and receiver 34, 35 connecting the computer with a motor which pivots the laser gun according to the computed angle.

It is also possible to provide the operator with a table showing the pivoting angles and to adjust the angular position of the laser beam gun accordingly by use of a protractor scale 36.

After the angular position of the laser beam gun has been thus adjusted, the receiver 5' is aligned with the adjusted laser beam 4' so that the beam impinges upon the receiver intermediate a pair of beam sensitive elements 37, 38 on the receiver, for instance photocells or thermoelectn'c elements. The aligi ment of the receiver 5' is effected in this embodiment together with the alignment of the track by laterally moving track engaging rollers 21 until the beam 4 hits the target between its beam sensitive elements, at which point the track has been lined in accordance with plan 26.

Upon conclusion of this stage, the receiver 5 is moved forwardly by distance y then y and so forth to distance y,,, in the direction of laser beam gun 2', the above-indicated adjustments being repeated after each intermittent forward move.

When the receiver 5' has been moved by distance y close to the laser beam gun into the position 39 indicated by broken lines, the laser beam gun must be moved forwardly into the region of a fixed track point forwardly of point 3, and the entire adjustment process is repeated for lining a succeeding track section, the fixed point 3 now becoming the point in relation to which receiver 5 is adjusted. Thus, the track 1 is continuously moved into the planned position indicated in broken lines, this alignment being possible not only in track curves but also in transition sections of the track, and, of course, in tangential track, according to the track map.

FIG. 3a shows a special control unit 8 which makes it unnecessary for the operator to determine the necessary data after each travel distance y and to feed them into the computer. This control unit operates as follows after each advance y of carriage 23:

The signal emitted from odometer 40 to indicate the traveled distance is transmitted by electric line 41 to a timing or synchronizing unit 42. The adjustor 43 sets the unit for a given traveled distance and, after this distance has been traveled, an impulse is transmitted by electric conductor 44 to amplifier 45. The amplified timing impulse is transmitted to stepping logic 47 by line 46 and unit 48 by line 46'. In response to the timing impulse, the unit 48 advances a punched or magnetic tape, or any other suitable information storage medium or element. Thus, the adjustment values for laser beam gun 2' and for receiver 5 corresponding to each length of the path of movement of receiver 5 are transmitted from the information storage medium to the stepping logic 47. The illustrated information storage medium is a punched card 48 which stores these values in dependence on the radius of the track curve section to be lined and the distance between the fixed points delimiting this section. The data transmitted by unit 48 are transformed by the stepping logic 47 into signals for controlling the adjustment motor 49 of laser beam gun 2 and the lateral adjustment of receiver 5, i.e. they are converted into a corresponding number of stepping impulses or a corresponding value of an analog voltage so that the motor 49 pivots the laser beam gun 2' by the desired angle.

FIG. 30 more clearly shows the adjustment motor 49 and the arrangement of the laser beam gun adjustment.

As shown in FIGS. 1 and 3, the stepping impulses may be transmitted from logic or computer 47 to motor 49 by an electrical conductor 9 or 33, or coded radio communication 34, 35.

After the adjustment, the laser beam receiver 5 is in the position 50 determined by the lining error of the track at this point and, accordingly, the laser beam will impinge on beam sensitive element 37 to produce a control signal. As shown in FIG. 3b, this control signal is transmitted with amplifier 51 and the amplified signal is transmitted by line 52 to solenoid hydraulic valve 54. The hydraulic valve is mounted in a hydraulic fluid pressure line 55 supplying hydraulic fluid from a source (not shown) to the jack 22, and operation of the valve causes the fluid to flow through branch line 55 into the jack cylinder chamber 56 so that the track is laterally moved into the planned position until the laser beam comes to impinge upon its target intermediate the elements 37 and 38, thus discontinuing the control signal, with the receiver 5 being in the corrected or lined position 39 shown in broken lines. This same adjustment occurs after each advance y y etc. until y As shown in FIG. 3b, the receiver 5' is mounted on a nut 57 on threaded spindle 57 which is rotated by a hand wheel so as to adjust the lateral position of the receiver transversely to the track in relation to fixed scale 20' until the distance between fixed point 7 and receiver 5' has the value x, determined by track map 26. The threaded spindle 57 is mounted on carriage 23 for mobility on track 1, the carriage running on flanged wheels which may be selectively pressed into engagement with a selected grade rail.

Similarly, as shown in FIG. 3c, the laser beam gun is also mounted on a nut on a threaded spindle to be laterally movable in relation to fixed scale 20 to assume the desired distance x between fixed point 3 and gun 2. An axle 58 is jounaled in the mounting nut and a pinion 59 is affixed to the pinion 59 and carries the laser beam gun. The output shaft of motor 49 carries a gear meshing with pinion 59 so that the pinion and base plate may be rotated to position the laser beam gun angularly. FIGS. 4 and 5 illustrate further embodiments operating according to the scheme of FIG. 1. In these embodiments, the position adjustment of the beam emitter and receiver in dependence on the differences in the ordinates during advance in the track curve is effected not by the angular adjustment of the beam emitter but by parallel movement of the receiver (FIG. 4) or emitter (FIG. 5).

In the apparatus of FIG. 4, a carriage 17" is mounted for mobility on track 1 in an uncorrected track section in the region of fixed track point 3 and carries the laser beam gun 2" whose position has been laterally adjusted at the beginning of the operation so that it has the distance x from the associated fixed point. After lateral adjustment, the laser beam gun is aligned with the laser beam target or sensor 5" receiving the beam and mounted adjacent track lining rollers 21" on track leveling, lining and tamping machine 61 for movement therewith along the track. Before this alignment, as previously described, the receiver 5" also is laterally adjusted in relation to fixed point 7 so that it has the distance x, therefrom. The laser beam target or sensor is mounted on a mobile carriage 23" in the region of the track gripping and lining rollers 21" which are laterally moved by jack 34 for lining the track. The machine 61 is mounted on two double-axled swivel trucks for mobility on track 1 consisting of rails 15, 16 and ties 64. As shown, the machine also carries a tamping unit 65 for tamping the ties, the schematically illustrated tamping unit being arranged to tamp two adjacent ties simultaneously. The track gripping rollers 66 serve to lift the track in a well known manner in respect of a reference system (not shown) to level the track while lining it by operation of jack 34" by control signals of beam sensitive elements 37", 38" in the manner illustrated in FIG. 3a.

The adjustment of the receiver to eliminate the differences in the ordinates at sucessive track points is effectuated in a manner similar to that described in connection with FIG. 3, i.e. the length of the traveled path is measured by odometer 40 whose signal is transmitted to motor 49" by control unit 8" via line 33" to rotate spindle 67 until the receiver 5 which is affixed to nut 53", has been laterally moved to the extent determined by control unit 8.

The adjustment of receiver 5" by motor 49" should be effectuated as rapidly as possible so as not to interfere with the speed of operation of the machine. This may be accomplished by the use of pneumatic, hydraulic or electro motors of high rotational speed but may also be achieved with a hydraulic jack. The effected lateral adjustment of receiver 5" is ascertained by a stop 68 at the other end of spindle 67 which transmits the measured distance via return line 68 to the control unit 8. Upon receipt of this information, the unit stops rotation of motor 49" so that the receiver is in the desired lateral position.

After this adjustment, the receiver is in alignment with the laser beam 4 under the control of the elements 37", 38". For a better understanding of the operation, two successive receiver positions 70 and 70 are indicated on the drawing, the full lines indicating the position of the receiver 5" after lateral adjustment by motor 49" and the broken lines showing its position after the track alignment.

In the schematic illustration of FIG. 5, the laser beam gun 2" and the receiver 5" are both laterally adjusted in relation to their respective associated fixed points 3 and 7 at the beginning of the operation. While the receiver advances on the track, together with the track lining rollers 21, towards the laser beam gun, the signal from odometer 40" transmits the distance of the traveled path via line 41" to control unit 8. The control unit is connected to motor 49" by line 33" to rotate spindle 71 and thus to move the nut 71 on the spindle until the laser beam gun, which is affixed to the nut, has reached the planned position in the direction of double-headed arrow 71".

One illustrative position 72 of the receiver is indicated on the drawing. In this receiver position, the difference of ordinates is compensated by laterally moving the laser beam gun from the position indicated in heavy lines to the position indicated in thin lines transversely of the track, whereupon the receiver is brought into alignment with the laser beam by being moved with the track into the lined position shown in broken lines. The adjustment operation for the receiver is the same as described in connection with FIG. 3b, wherefore this structure has been shown only by a rectangle in broken lines.

FIGS. 6 to 8 illustrate embodiments for use with the scheme shown in FIG. 2.

The actual position of rails l5, 16 of track 1 is shown in full lines while their planned position is indicated in broken lines 16' in FIG. 6. The front end of a track leveling, lining and tamping machine 61' is shown to be mounted for mobility on track 1 by undercarriages 63 (only the front axle being shown). The machine may be similar to that of FIG. 4, including track lining rollers 23 and a reference system 12' for lining the track, the illustrated reference system being the well-known twochord system comprising a long chord 73 and a short chord 74 which are anchored to carriages 75 and 75', respectively, the carriages being pressed selectively into contact with a selected grade rail, i.e. outer curve rail 15. The carriage 75 runs under the machine frame and may be lifted off the track as well as being pressed into contact with the grade rail by pneumatic jacks. The forward carriage 75 is attached to the forward end of the machine frame by two spacing rods 76 so that it runs in an uncorrected section of the track, this carriage constituting the forward end point of the long chord of the reference system. The laser beam target or sensor 5"" is laterally movably mounted on carriage 75 so that its position may be adjusted transversely of the track in relation to fixed point 7 of the track as well as for compensation of changes in the ordinate in the track curve so that the lining errors occurring at the forward end point of the reference system do not disadvantageously influence the lining operation.

A double-axled carriage 17' is mounted for mobility on the track in the region of second fixed track point 3 and carries the laser beam gun 2", a pneumatic or hydraulic jack 79 being arranged for adjusting the axles 77 and 78 of the carriage so that one of the flanged wheels of axle 77 engages grade rail 15.

At the beginning of the operation, the laser beam gun is focussed on the target to establish a laser reference beam 4 for target 5".

This machine operates as follows:

The machine is advanced to bring the laser beam receiver into consecutive positions 80, 80', 80", the length of the path of the movement of the receiver being measured each time by odometer 40 which transmits a corresponding signal to control unit 8 via line 41. On the basis of the stored track data, the control unit controls the tranverse movement of the receiver by operating motor 49' which rotates threaded spindle 82 to move nut 82', which carries the beam receiver, until the receiver is in the planned position.

In the position 80, for instance, the laser beam 4" will impinge on beam sensitive element 37 of the receiver target, causing a control signal to be transmitted by line 52 to motor 83 which rotates the threaded spindle until the receiver 5"", together with the end point of long reference chord 73, is moved into alignment with the laser beam. After this alignment, the track is lined with the aid of reference system 12 in a well known manner. The prior adjustment of the forward end point of the reference system to move it into the desired or planned position of the track assures the exact lining of the track by the track lining rollers 21' since the rear end points of the reference chords 73 and 74 are already in a lined section of the track.

The embodiment of FIG. 7 is similar to that of FIG. 6 but the constantly changing ordinates in the curve are compensated by the angular adjustment of the laser beam gun 2. Again, the signal from odometer 40 is transmitted to the control unit 8 by line 41, and the values for the angular adjustment of the laser beam gun 2 are transmitted to the gun from the control unit via line 33. Since the laser beam unit 84 is identical with that of FIG. 3c, it has been shown only by a box in broken lines. The forward end point of reference line 85 of a conventional reference system 12 is anchored to carriage 75 which carries the laser beam target A measuring bogie 75 is mounted in the region of the lining rollers 21', a potentiometer 86 on the bogie indicating the position of the reference line 85 in relation to the bogie and thus controlling the operation of the lining rollers. Reference systems of this and the twochord type are well known and form no part of the present invention.

Starting from the region of fixed track point 7, the laser beam receiver 5" is moved towards fixed track point 3 in whose region the laser beam gun 2 has been positioned. At each track point requiring alignment of the forward end point of reference line 85, the laser beam gun is first pivoted into the desiredv position, whereupon the receiver 5" is aligned with the laser reference beam 4'. As shown at 87, this is effected by light-sensitive elements 37, 38 on the receiver, which controls operation of motor 88 via line 52' so that the spindle 89 is rotated by the motor until the receiver, together with the anchor 90 of the end point of the reference line 85, is transversely moved to a position where the laser beam impinges thereon intermediate elements 37 and 38, the receiver and anchor 90 being affixed to nut 89' moving on the spindle.

In the embodiment of FIG. 8, the apparatus is used with a two-chord reference system 12. As in FIG. 6, the end point of short chord 74 is anchored to carriage 75 while the end point of long chord 74 is anchored to carriage 75' which also carries the transversely adjustable laser beam target 5". The chain-dotted line 91 indicates the position of the long reference chord and the chain-dotted line 91 the position of the laser beam 4" during the lateral adjustment of the receiver 5" in relation to fixed track point 7 so that it is spaced therefrom by distance x,. The full lines indicate the positions of the long reference chord and the laser beam during operation between fixed track points 7 and 3. Again, the odometer 40 transmits signals corresponding to the traveled distances to the control unit 8 via line 41 and unit 8 transmits control signals via line 33 to move the laser beam gun transversely of the track in the planned position, shown at 92. After this adjustment, the emitted laser beam serves as reference for target 5" which is in the position 93 before the alignment thereof, as indicated in full lines. Box 87 shows how rotation of threaded spindle 89 laterally moves receiver 5 until it and the end point of long chord 73 have reached the desired or planned position 94, whereupon the chord 73 assumes position 95 shown in broken lines.

After the long chord 73 of the lining reference system has thus been accurately positioned, the lining into the desired or planned position can be effected with great accuracy. Since the laser beam gun adjustment operation has been fully shown and described in connection with FIG. 5, it has been indicated on FIG. 8 only by box 96.

Of course, it is possible to store any or all of the data used for adjustment of the laser beam gun and/or receiver on the basis of a computerized track survey, and then to use the stored information in a subsequent lining operation. Also, any suitable means, including hydraulic jacks, may be used for the lateral and/or angular movements of the gun and receiver, such jacks being operated by pulses of hydraulic fluid corresponding to the length of the path of movement of the receiver on the track, such moving means operating with great speed and thus being particularly useful in rapid lining or surveying operations. It is also possible to ascertain the data for the adjustment of the end point of the lining reference system and the lateral movement of the lining mechanism beforehand and to store this information, these movements being controlled by the stored data in a subsequent operation.

We claim:

1. In a method of lining a track in respect of a laser reference beam forming an accurate chord in relation to the track, wherein a stationary laser beam emitter and a mobile laser beam receiver are laterally adjusted in relation to associated fixed points of the track to eliminate any lining error at the associated fixed points whereby the lateral distances between the emitter and receiver correspond to a desired distance, and the reference beam is obtained by focussing the laser beam on the adjusted receiver: the steps of 1. moving the laser beam receiver along the track towards the laser beam emitter by a predetermined distance after the laser beam has been focussed,

2. adjusting the relative position of the emitter to receiver in dependence on the distance of movement of the receiver and a planned lateral position of the track until the distance between planned lateral track position and the reference beam as well as the reference beam receiver has a planned value in the adjusted position.

3. determining the value of the lining error from the planned lateral position after the relative position adjustment of the emitter to receiver, and

4. moving the laser beam receiver by another predetermined distance towards the laser beam emitter.

2. In the method of claim 1,. the step of moving the laser beam receiver laterally transversely to the track during the movement of the laser beam receiver towards the laser beam emitter until the distance between the receiver and a grade rail of the track substantially corresponds to the distance between the reference beam and the planned lateral position of the grade rail, whereupon the value of the lining error is determined.

3. In the method of claim 2, the step of correcting the track by the determined value of the lining error.

4. In the method of claim 1, the step of moving the laser beam receiver laterally transversely to the track after the movement of the laser beam receiver towards the laser beam .emitter until the distance between the receiver and a grade rail of the track substantially corresponds to the distance between the reference beam and the planned lateral position of the grade rail, whereupon the value of'the lining error is determined.

5. In the method of claim 4, the step of laterally correcting the track by the determined lining error.

6. In the method of claim 1, the step of pivoting the emitter about an axis extending substantially perpendicularly to the track plane during the movement of the laser beam receiver towards the laser beam emitter until the distance between the reference beam and a grade rail of the track substantially corresponds to the planned distance therebetween, whereupon the value of the lining error is determined.

7. In the method claim 6, the step of correcting the track by the determined value of the lining error.

8. In the method of claim 1, the step of pivoting the emitter about an axis extending substantially perpendicularly to the track plane after the movement of the laser beam receiver towards the laser beam emitter until the distance between the reference beam and a grade rail of the track substantially corresponds to the planned distance therebetween, whereupon the value of the lining error is determined.

9. In the method of claim 8, the step of correcting the track by the determined value of lining error.

10. In the method of claim 1, the step of storing the determined values of adjustment of the receiver and/or emitter in relation to a grade rail of the track.

11. In the method of claim 1, the step of moving the emitter laterally transversely to the track during the movement of the laser beam receiver towards the laser beam emitter until the distance between the reference beam and a grade rail of the track substantially corresponds to the planned distance therebetween, whereupon the value of the lining error is determined.

12. In the method of claim 1, the step of moving the emitter laterally transversely to the track after the movement of the laser beam receiver towards the laser beam emitter until the distance between the reference beam and a grade rail of the track substantially corresponds to the planned distance therebetween, whereupon the value of the lining error is determined. 

1. In a method of lining a track in respect of a laser reference beam forming an accurate chord in relation to the track, wherein a stationary laser beam emitter and a mobile laser beam receiver are laterally adjusted in relation to associated fixed points of the track to eliminate any lining error at the associated fixed points whereby the lateral distances between the emitter and receiver correspond to a desired distance, and the reference beam is obtained by focussing the laser beam on the adjusted receiver: the steps of
 1. moving the laser beam receiver along the track towards the laser beam emitter by a predetermined distance after the laser beam has been focussed,
 2. adjusting the relative position of the emitter to receiver in dependence on the distance of movement of the receiver and a planned lateral position of the track until the distance between planned lateral track position and the reference beam as well as the reference beam receiver has a planned value in the adjusted position.
 3. determining the value of the lining error from the planned lateral position after the relative position adjustment of the emitter to receiver, and
 4. moving the laser beam receiver by another predetermined distance towards the laser beam emitter.
 2. adjusting the relative position of the emitter to receiver in dependence on the distance of movement of the receiver and a planned lateral position of the track until the distance between planned lateral track position and the reference beam as well as the reference beam receiver has a planned value in the adjusted position.
 2. In the method of claim 1, the step of moving the laser beam receiver laterally transversely to the track during the movement of the laser beam receiver towards the laser beam emitter until the distance between the receiver and a grade rail of the track substantially corresponds to the distance between the reference beam and the planned lateral position of the grade rail, whereupon the value of the lining error is determined.
 3. In the method of claim 2, the step of correcting the track by the determined value of the lining error.
 3. determining the value of the lining error from the planned lateral position after the relative position adjustment of the emitter to receiver, and
 4. moving the laser beam receiver by another predetermined distance towards the laser beam emitter.
 4. In the method of claim 1, the step of moving the laser beam receiver laterally transversely to the track after the movement of the laser beam receiver towards the laser beam . . . emitter until the distance between the receiver and a grade rail of the track substantially corresponds to the distance between the reference beam and the planned lateral position of the grade rail, whereupon the value of the lining error is determined.
 5. In the method of claim 4, the step of laterally correcting the track by the determined lining error.
 6. In the method of claim 1, the step of pivoting the emitter about an axis extending substantially perpendicularly to the track plane during the movement of the laser beam receiver towards the laser beam emitter until the distance between the reference beam and a grade rail of the track substantially corresponds to the planned distance therebetween, whereupon the value of the lining error is determined.
 7. In the method claim 6, the step of correcting the track by the determined value of the lining error.
 8. In the method of claim 1, the step of pivoting the emitter about an axis extending substantially perpendicularly to the track plane after the movement of the laser beam receiver towards the laser beam emitter until the distance between the reference beam and a grade rail of the track substantially corresponds to the planned distance therebetween, whereupon the value of the lining error is determined.
 9. In the method of claim 8, the step of correcting the track by the determined value of lining error.
 10. In the method of claim 1, the step of storing the determined values of adjustment of the receiver and/or emitter in relation to a grade rail of the track.
 11. In the method of claim 1, the step of moving the emitter laterally transversely to the track during the movement of the laser beam receiver towards the laser beam emitter until the distance between the reference beam and a grade rail of the track substantially corresponds to the planned distance therebetween, whereupon the value of the lining error is determined.
 12. In the method of claim 1, the step of moving the emitter laterally transversely to the track after the movement of the laser beam receiver towards the laser beam emitter until the distance between the reference beam and a grade rail of the track substantially corresponds to the planned distance therebetween, whereupon the value of the lining error is determined. 